Photographic developer and process of making same.



UNlTED STATES PATENT OFFICE.

ASSIGNORS TO FARBENFABRIKEN OF ELBERFELD CO., OF NEW YORK N. Y., ACORPORATION OF NEW YORK.

PHOTOGRAPHIC DEVELOPER AND PROCESS OF MAKING SAME.

SPECIFICATION forming part of Letters Patent N 0. 703,243, dated J une24, 1902.

Application filed July 1'7, 1901. Serial No. 68,676. (Specimens) To allwhom it may concern.-

Be it known that we, ARTHUR EIOHENGRUN and THEODOR BECKER, doctors ofphilosophy, chemists, residing at Elberfeld, Germany,

5 (assignors to the FARBENFABRIKEN on EL- BERFELD 00., of New York,)have invented a new and useful Photographic Developer and Process ofMaking Same; and we hereby declare the following to be a clear and exactde- 16 scription of our invention.

We have found that new products of addition from polyhydroxylderivatives of aromatic bodies can be obtained by the action of theseco1npoundssuch as pyrogallol, py-

rocatechin resorcin, or the like--on aliphatic or nitrogen bases, suchas methylamin, dimethylamin, or the like. The process forpreparing thesecompounds can be carried out by melting a mixture of equimolecularproporo tions of the two components or by causing the same to react oneach other in the presence of a suitable solvent, such as water,alcohol,ben- 'zene, or the like. The new bodies thus obtained arecrystalline compounds, soluble in e 5 water, which possess an alkalinereaction. By

the action of caustic alkalies they are split up into their components.The new bodies will be used as photographic developers.

In carrying out the new process practically we can proceed as follows,the parts being by 4o arated in the mixture.

weight: A watery solution of one hundred and twenty-six parts ofpyrogallol is added to two hundred and twenty-five parts of atwenty-per-cent. solution of dimethylamin and the resulting mixture isthen allowed to stand at the ordinary temperature, a contact with theair being avoided the while. After some time the liquid becomes hotspontaneously, a precipitate of large prisms being sep- When thereaction is finished, the precipitate is filtered off, contact with theair being avoided. The new additional product, having the formulainsoluble in ether. It has the melting-point 163 contigrade.

The process proceeds in an analogous manner if other aliphatic amins areemployed, such as trimethylamin, monomethylamin, or the like. Otherphenols or derivatives there of containing several hydroxy groups reactin an analogous manner-such as resorcin, pyrocatechin, phenolcarboxylicacids, or the like.

The additional product obtained from resorcin and dimethylamin melts at82 centigrade. The additional compound produced from dimethylamin andpyrocatechin melts at 115 centigrade. The compound obtained fromdimethylamin and the methylic ether of gallic acid melts at 164centigrade. The dimethylaminethylic ether of this acid melts at 79centigrade and free from water at about 122 centigrade, While thecombination dimethylamin-ga1lacetophenone has the melting-point 156centigrade.

Having now described our invention an in what manner the same is to beperformed, what we claim as new, and desire to secure by Letters Patent,is-

l. The process for producing new products of addition from polyhydroxylderivatives of the benzene series which process consists in firsttreating these compounds with nitrogen bases of the aliphatic series andthen isolating the resulting bodies from the reaction mixture,substantially as hereinbefore described.

2. The process for producing a new product of addition beingpyrogalloldimethylamin of the formula:

0 11,4011),-muon by first treating pyrogallol with dimethylamin and thenisolating the new compound from the reaction mixture, substantially ashereinbefore described.

3. The herein-described new products of addition from polyhydroxylderivatives of the benzene series with nitrogen bases of the aliphaticseries which are crystalline substances, soluble in water and possessingan alkaline reaction, being split up into their components by the actionof caustic alkalies, substantially as hercinbefore described.

4. The herein-described pyrogallol-dime- I In testimony whereof we havesigned 0111" I6 thylamin having the formula: I names in the presence oftwo subscribing witnesses.

O H (OH) NH(OH A E O N UN Q RTHUR l I-IE GR 5 wlneh 1s a crystalllnepowder 1116113113 at 163 eentigrade which is easily soluble 1; Water,THEODOR BECKER soluble with difficulty in alcohol and insolu-VVianesses:

ble in ether, substantially as hereinbefore l J. A. RITTERSHAUS,

, A. SOHADDE, Jr.

described.

